环境：CentOS 6.5
[root@CentOS ~]# yum -y localinstall epel-release-6-8.noarch.rpm
安装完成后，会在/etc/yum.repos.d目录下生成两个文件（epel-testing.repo和epel.repo）
[root@CentOS ~]# ls /etc/yum.repos.d/ CentOS-Base.repo CentOS-fasttrack.repo CentOS-Vault.repo epel-testing.repo CentOS-Debuginfo.repo CentOS-Media.repo epel.repo service.repo [root@CentOS ~]# [root@CentOS ~]# yum list|grep epel|wc -l Repository base is listed more than once in the configuration 11343 [root@CentOS ~]#
关闭epel时：
[root@CentOS yum.repos.d]# sed -i '/enabled/s/1/0/' epel.repo [root@CentOS yum.repos.d]# yum list|grep nagios Repository base is listed more than once in the configuration [root@CentOS yum.repos.d]#
打开epel时：
[root@CentOS yum.repos.d]# sed -i '/enabled/s/0/1/' epel.repo [root@CentOS yum.repos.d]# yum list|grep nagios|wc -l Repository base is listed more than once in the configuration 77 [root@CentOS yum.repos.d]#
